Prolactin is the hormone responsible for milk production and has been dubbed a “natural birth control” for breastfeeding women. However, high levels of prolactin, or hyperprolactinemia, is undesirable in women trying to conceive. In both of these instances, prolactin inhibits ovulation.

Researchers on this study led by Jacques Young and Nadine Binart of the Bicêtre Hospital in France, administered prolactin treatments to mice in an effort to mimic the infertility condition hyperprolactinemia. Hyperprolactinemia prevents the appropriate release of hormones which under normal circumstances, would trigger ovulation.

The mice were then given injections of a kisspeptin, a hormone which restores the release of gonadotropin releasing hormone (GnRH), and signals ovulation to occur.

These findings might provide an alternative treatment for this type of infertility, though testing is warranted in human subjects.